Connector plug



Nov. 7, 1944.- c. H. JUDISCH 2,362,074

CONNECTOR PLUG FiledAug. 30, 1941 III I lNVENTOR Czar? H Judisciz/ '"l D Anqusvs Patented Nov. 7, 1944 CONNECTOR PLUG Carl H. Judisch, New Haven, Conn, 'assignor to The Whitney BlakeXCompany, I New Haven, Conn., a corporation of Connecticut- Application August 30, 1941, Serial No. 408,975 i 2 Claims. (01. 1vs-3e1) This invention relates to connector plugs, and is a continuation in part of my copending application, Serial No, 363,996, filed November 2, 1940.

Until recently, connector plugs have been generally formed of some hard insulating material such as Bakelite. The contact prongs were fixed to the body of the plug by rivets or the like and carried some securing means, such as screws,

. by means of which conductors were attached to conductor cord-receiving cavity. In these plugs,

means are formed within the passages, generally on the walls of the same, for engaging means carried by the prongs to hold the latter in their proper positions within the passages when mounted therein.

The means within the passages often restricted thesamemaking it difficult to insert the prongs X withinthe passages, or the passages themselves were so formed relative to the plug body that it was diflicult to mount the prongs properly within the same. This increased assembly costs, for it was necessary to employ in the assembly operation costly machines having a complicated cycle of operations for inserting the contact prongs within the passages.

The assembly operation of the previously proposed resilient plugs generally distorted the material of the plug body so that the material necessarily had to be formed of a relatively expensive grade rubber which is readily distensible. Accordingly, not only were assembly costs relatively high but the manufacturing costs as well.

The plug of the presentinvention, although itis formed with passages for receiving the contact prongs and the wall of the passages formed with v means to cooperate with the contact prongs to ,through the plug body in converging straight line paths of movement without distending the material of the body to pick up and pull back into the passages on their return movement a pair of contact prongs.

One wall of each passage,'in the preferred form of the present invention, is formed with a pair of spaced notches for taking tangs projecting from one face of each contact prong. The passages are not restricted, for the notches form recessed seats, on the walls of the passage and the prongs are readily mounted therein. The tangs, as they engagethe'recessed seats formed bythe notches prevent longitudinal movement of the prongs in the passages and anchor the same therein.

It is preferred to assemble the plug'of the present invention with the prongs attached to conductors by a machine such as disclosed and claimed in my copending application, Serial No. 340,951.,filed June 17, 1940, although the plug may be assembled by other machines or even by hand.

The machine of my copending application comprises a pair of pull arms moving in converging but straight line paths of movement through'the plug body to a position wherein the free ends are exposed at the rear of'the plug so that the contact rongs may be mounted to hooks formed thereon and pulled back in diverging paths into proper position in the passages.

To permit the hooks of thepull arms to pass through the plug of the presentinvention, the wall of each passage is formed with a longitudinally extending groove coextensive therewith. The grooves preferably are substantially as wid as the pull arms and permit the arms to enter and move freely through the plug body without distorting the material of the same.

As the prongs can be readily mounted within the passages of the plug in a minimum of assembly operations, the assembly costs of the plug of the present invention are relatively low and as the plug body is butlittlewdistorted during the assembly operation, it can be formed of a cheaper grade ofrubber than heretofore possible.

Other features and advantages will hereinafter appear. i

In the accompanying drawing:

Figure 1 is a perspective view showing the con nector plug of the present invention with the contact prongs mounted therein. 1 1

Fig. 2 is a sectional view showing a fragmentary .part ofthe pull arms after the same have been passed throughthe plug.

Fig. 3 is a sectional view of the connector plug showing the positionof the contact prongs just prior to their disengagement from the pull arms which have noW been retracted from the plug.

Fig. 4 is a sectional view of the assembled plug illustrated in Fig. 1 showing the contact prongs seated in their passages.

The connector plug of the present invention comprises a body Ill of resilient insulating material such as rubber or the "like. The plug is formedduring its molding operation with a conductor cord-receiving cavity H opening onto one face of the plug and a pair of spaced contact prong-receiving passages I2 leading from the cavity H to the opposite face of the plug.

The one wall of each passage "I 2 715 provided with a pair of notches l3 and I4 respectively forming recessed seats spaced longitudinally of the passages and adapted to receive spaced tangs l5 and I6 projecting from the one face of the contact prongs IT to lock the contact prongs in their proper .position within the-passages .l 2 after they have been inserted therein.

The notches l3 and I4 do not restrict'the passages which are of .such size and shape relative to the size and .sh-ape of the conductor-receiving cavity 44, referring snow to :Fig. that a ,pair of rigid :pull arms, :such :as disclosed .-in my aboveidentified 'copending application, may be simultaneously massed through the :plug body in converging straight line :paths of movement with little, if any, distention ::of the material of the body.

'The pulharm s 3'83'3'1'6 formed zadc'acent the ifITEE ends thereof with hooks l9 to permit thecontact rongs ill to be mounted to the same through eyes 20 formediadjacent the one end efthe contact prongs.

"Io permit the hooks 1E9 11f the :pull arms to pass through the rplug without ngoug ingtthe walls of the :passages, :the wall :O'feachpassage opposite the wall provided with the recessed seats'is formed with .a longitudinally extending groove 24 coextensive therewith. The grooves Z 'L'pre'ferably, :are substantially as "wide as the 1311113111118 ?|'B and permit the 'arms to move freely through the plug body without imarring the walls of the passages ioridistortirrg the material of the body.

When "the pull arms 18 have been moved to the position shown in an-operator mounts to the exposed end f each pull arm a contact prong :If! to which has been secured a conductor 2 2 or .a twin conductor cord 23, whereupon the pull arms are then retracted in diverging paths to -pull the .contact prongs into proper position in the prong-receiving passages.

'Ihettangs I35 and it oi' the contact prongs H, as the latter are pulled into the passagea enter the rnotc'hes IE3 and 1'4 and seat therein. The

plug body :is .somewhat distended by the move- .ment -'of the icon'tac't prongs through the passages :but this 'may be reduced by 'form'ing the tangs to iplDllBCt toward "one another.

The rnotdhes 1 4 -are undercut relative to the walls or the passages 'l 2 andtangs *I'G will enter and seat there'inas the-Gangs l5 are entering and seating in the notches l3, the seats of which are normal to the walls of thepassages T2. It will be 'seen, refer-ring now to Fig. '3, that tangs IE will seat in their respective notches slightly 'in advance of the entrance of tangs 15 into the notches P3.

In the embodiment of the invention as now preferred, the tangs l5 are inotm'oved into their proper position until after thexprongs .have been disengaged from "the arms 18 "a'fter the latter the prongs into their position as shown in Fig. 4

with the 'tangs projected into their respective notches.

The inner ends of the prongs are offset slightly to allow the ends of the prongs to move past the corners 25 at the junctions of the passages l2 with thecavity 1 'As the ofiset portions of the prongs engage the corners 25 when the prongs 'aredntheir'proper position within the passages,

any movement of the prongs which might tend -to move the tangs Hi from the 'notches I4 is resisted. 'This brings about a firmer anchorage of the prongs within the passages.

In the particular embodiment of "the present invention illustratedthe formation of the 'tangs not onlyreduces the distention of the plug body asthe'contact prongs are moved through'the passages, but also results in afirmerianch'orage of the contact prongs within the passages. This is brought about 'by the "fact that the tangs are "spaced apart 'a distance slightly less than'the distance between the seats -form'edby the notches so that the material of thebody intermediate the seats 'is somewhat compressed after "the 'tangs have seated within 't'henotches 'This "does not complicate assembly operationsi'for the tangs I'B will readily seat in the notches I'd as tan'gs l5 are entering thenotches l3.

Topreventtheinner-endsof the contact prongs from coming into engagement with each other, the portion of the body intermediate the parssages I2 is extended into the cavity II to form a separating finger '26. The finger 1'2'6 holds the inner ends of the contactprongs against accidental engagement and thus prevents the occurrence of short circuits-within 'the'plug.

The plug of the present invention is not 'difficult to mold, for as seen, no complicated shouldered formations are used "for "holding the contact prongs seatedwith'in the passages. This reduces manufacturing costs which are further reduced as the plug'canbe assembledwithhut'little distortion and need not be 'formed of a relatively expensive grade of rubber suificientlyresilient to permit the distortion generally present during theassemblyopera tion of the'previously'proposed plugs.

As movement of the pull arms through the plug is not hindered by any restrictions in the passages and .as the pull arms move freely through the pluginstraight line paths of move} ment, the plug of the present inventionmay'be assembled in a minimum of assembly operations.

Variations and modifications may be made within the scope of this invention .and portions being simultaneously insertable through the cavity and into said passages; and tangs spaced longitudinally of the contact prongs fitting in said notches for locking the contact prongs in said passages when the same are in the proper assembled position in the body, the passages being of such size and shape relative to the size and shape of said cavity as to permit a pair of pulling members having prong mounting means on the outer faces thereof to enter the plug by said grooves and pass through the plug in converging straight line paths of movement without distorting the material thereof whereby said prongs may be v mounted to said mounting means and pulled back into proper assembled position in said passages as the pulling members are retracted in diverging straight line paths of movement, the mounting means riding in said grooves during at least a portion of the movements of said pulling members.

2. In a connector plug of the type described,

a one-piece body of resilient material having a spaced longitudinally thereof, the innermost seat being undercut relative to said wall of the passage, the other of said seats extending normal thereto; a vpair of contact prongs each having one conductor of a twin conductor cord secured thereto, the passages including said grooves forming with said cavity a pair of converging unrestricted channels extending through said body whereby a pair of pull arms having prong mounting means on the opposite faces thereof may be freely passed through said body in converging straight line paths of movement to expose said I mounting means at the rear of said body to permit said prongs to be secured thereto and pulled back through said cavity and into the passages, said grooves receiving the prong mounting means of said pull arms during at least a portion of the movements thereof to prevent the mounting means from gouging the walls of the passages; and a pair of tangs formed on each prong and adapted to engage said seat, said tangs angularly extending toward each other and being spaced apart a distance less than that between the seats, thereby compressing the material of said plug body intermediate the seats to lock the prongs against longitudinal movement in either direction relative to said passages after said prongs have been pulled therein.

CARL H. JUDISCH. 

